Device for storing a thread portion

ABSTRACT

The present invention relates to a device for a weaving loom for storing a thread piece or portion of varying length and which is subjected to the action of a stream of fluid such as air endeavoring to retain the said thread end between two predetermined locations, in the form of a thread loop, there being effected continuous delivery of the thread at one of the said predetermined locations and, at the other of the said predetermined locations, periodic drawing-off of the thread when the latter is inserted into a shed of the loom with the aid of pick inserter means.

United States Patent 1191 1111 3,865,149

Keldany 1 Feb. 11, 1975 DEVICE FOR STORING A THREAD 3,575,217 4/1971 Pfarrwaller 139/122 3,580,444 8/1968 Mullekom 139/122 PORTION [75] lnventor: Rachid Keldany, Egg/Zwich, Switzerland [73] Assignee: Ruti Machinery Works, Ltd.,

Ruti/Zwich, Switzerland [22] Filed: June 4, 1973 [21] Appl. No.: 366,317

[30] Foreign Application Priority Data June 16, 1972 Switzerland 9(l8l/72 [52] US. Cl. 139/122 R, 226/97, 139/127 P [51] llnt. Cl D03d 47/34 [58] Field of Search 139/122 R, 122 H, 127 P; 226/117, 118, 97; 242/182 [56] References Cited UNITED STATES PATENTS 3,303,857 2/1967 Scheffel l39/l22 Primary ExaminerHenry S. .laudon Attorney, Age/1!, 0r FirmDonald D Denton [57} ABSTRACT The present invention relates to a device for a weaving loom for storing a thread piece or portion of varying length and which is subjected to the action of a stream of fluid such as air endeavoring to retain the said thread end between two predetermined locations, in the form of a thread loop, there being effected continuous delivery of the thread at one of the said predetermined locations and, at the other of the said predetermined locations, periodic drawing-off of the thread when the latter is inserted into a shed of the loom with the aid of pick inserter means.

7 Claims, 4 Drawing Figures PATENIED FEBH i975 SHEET 2 OF 2 DEVICE FOR STORING A THREAD PORTION BACKGROUND OF THE INVENTION It is known to manufacture a fabric by extracting weft threads from a supply of weft thread and inserting them individually into the shed. If the said threads are directly taken from the supply of weft thread, then there takes place at the commencement of the picking of each individual weft thread, a sudden movement pulling the weft thread away from the supply, and this is undesirable for the thread.

In order to mitigate the sudden or jerky" character of the thread unwinding, recourse may be had, for example, to an arrangement whereby, with the aid of a continuously rotating drum, the weft thread is taken-off as uniformly as possible from the supply and wound onto the drum from which unwinding for insertion of the pick can more readily be effected. However, unwinding from the said drum still requires a certain amount of force.

For various weaving processes, such as insertion of the weft thread by means of a jet of air or water of the like, this force is excessivly large. However, also in other looms, it is always desired that the pulling-away of the weft thread should be effected as readily as possible. A known method requiring little pull-away force consists in that the weft thread end to be inserted is stored in an elongate tube in which obtains reduced atmospheric pressure retaining the thread as a loop. This arrangement has the disadvantages that the maintenance of reduced pressure requires a relatively large amount of energy and that, on inserting the weft thread into the shed, the pick must be displaced completely against the air stream acting on it due to the reduced pressure. Furthermore, these storage devices require a plurality of deflecting locations for the weft thread, at which said deflecting locations the said weft thread is, on pull-away, once again subjected to a deceleration effect.

The closest prior art known to the applicant in connection with this application is the following:

U.S. Pat. Nos. 3,250,299; 3,589,405; British Pat. No.

SUMMARY OF THE INVENTION According to the present invention, these disadvantages are obviated. The present invention is characterized in a device or arrangement that has an injector means that generates, at one of two predetermined locations, a fluid stream serving to convey continuously a thread and by means of which the said thread is retained as a loop having two legs or limbs, and in that there is available, at least at the side of that leg of the loop which is located on the side of the other predetermined location, a free space extending over the entire length of the said loop leg.

The invention will now be discussed in greater detail with reference to examples of embodiments and with reference to the drawings, in which:

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a further embodiment of the present invention showing the use of spaced plates and an auxiliary fluid means used in the forming of the thread loop;

FIG. 2 is a cross-section taken along the line 22 of FIG. 1;

FIG. 3 is a still further embodiment of the invention showing the use of spaced 'plates in the forming of the thread loop; and

FIG. 4 is a variant of the embodiment according to FIGS. 1 and 2, in which the spaced plates are curved.

DESCRIPTION OF PREFERRED EMBODIMENTS In the following description of preferred embodiments, like parts will have like numbers.

According to FIG. 1, a weft thread 11 travels from a supply bobbin 12 of weft threads to an air injector 14 into which air is fed in the direction of arrow 15. The thread 11 is guided through a tube 16 of the injector 14. The air flow flowing through the injector 14 endeavors to permanently suck the thread 11 out of the tube 16 in the direction of arrow 22 and to blow it forward where it is formed into the shape of a loop 17.

During further travel, the thread II passes through an eyelet 18, then through a controllable yarn brake or thread gripper 19 and a water-jet nozzle 20, and is then inserted by means of the nozzle into shed 21 of a loom.

The air jet emerging out of the injector 14 is guided by two elongate plates 25, 26. The plates 25, 26 may be formed by bending an elongate plate about its centerline 30 extending in the longitudinal direction to form a pinched Ulike cross-sectional shape to form an elongated interspace 31, as is shown in FIG. 2.

The air jet for forming the thread loop 17 expands laterally out of a slot 27. The result of this is that the loop apex 35 also is located continuously externally of the interspace available between the plates 25, 26. This is desirable since, thereby, the air stream of the injector 14 on the curved portion of the thread at the thread loop apex 35 is weak, so that the force acting on the thread loop 17 of the air stream of the injector 14 is relatively small. Thereby, the weft thread inserter nozzle 20 requires less energy for inserting the weft thread or, if the capacity of the said nozzle 20 remains unchanged, an increased insertion velocity is obtained for the weft thread. It should be noted that the delivery of the thread into the storage zoneis effected to a substantial degree due to the injector effect, i.e. due to the suction in the tube 16, and therefore the tractive force in the zone ofthe thread loop apex 35 can be kept at a low level.

If a weft thread portion or piece is to be inserted into the shed 21, then the nozzle 20 produces a short, powerful water jet. Simultaneously, the yarn brake 19 opens. Due to the action of the water jet, the thread end disposed in the water nozzle 20 and the end of the thread 11 projecting-out at the front end of the nozzle 20 are engaged and the weft thread 11 accompanied by pulling-out of the loop 17 is inserted into the shed 21, thereby shortening the legs 17, '17" of the loop 17. The thread 11 travels for a short instant from the front portion of the injector 14 more or less rectilinearly to the eyelet 18. As soon as the gripper 19 closes, the loop 17 once again commences to be formed until the legs 17', 17" have been elongated, and on the nextfollowing insertion of a weft thread, by means of the nozzle 20 or the weft inserter means 20, the loop 17 is once again consumed.

vOn inserting the weft thread into the shed, the loop leg 17 located on the side of the eyelet 18 is first of all pulled towards the eyelet 18. The said leg 17" is located externally of the air jet flowing in the direction 22, so that the air jet, during insertion of the weft thread, does not exert any counterforce on the leg 17". Additionally, pull-out of the loop takes place in such manner that the loop legs 17, 17" travel, according to FIG. 1, towards the right, out of the flow of the air stream flowing in the direction of arrow 22. Thereby, on pull-out of the loop 17, the counterforce produced by the said air stream becomes relatively small and, thereby, a higher insertion velocity for the weft thread 11 is achieved. Thus, it is an essential feature of the present invention that the space on the right-hand side of the air stream flowing in the direction of the arrow 22, i.e., on the side of the eyelet 18 of the said air stream, is free, in order that the weft thread may on pulling out of the loop 17 be able to travel unhindered towards the right and out of the said air stream (see FIG. 1).

It will be appreciated that the loop 17 has one portion or leg 17' that ends adjacent to the injector means 14 and defines a first predetermined location and the other leg portion 17" ends adjacent to the eyelet 18 which defines a second predetermined location.

Depending on the given circumstances, the air stream flowing out of the injector 14 may be directed upwardly, downwardly, horizontally, or also obliquely. Above all in the case of the two last-mentioned variations, it may be advisable to provide the thread loop 17 with supplementary retaining means, in order to prevent undesirable catching of the loop 17.

Referring again to the embodiment according to FIG. 1, the conditions are such that, in consequence of the lateral expansion of the air some distance from the injector 14, the leg 17 also can be blown out of the interspace between the plates 25, 26. In such a case, a satisfactory loop shape will no longer be afforded. In order to avoid such an undesirable mode of operation, apertures 28 are formed in the bent-over portion located opposite the slot 27. The said bent-over portion is closed in the vicinity of the injector 14. The apertures 28 formed some distance from the said injector have the effect that the unilateral expansion of the air jet through the slot 27 is compensated for. Thereby, the leg 17 is, over a relatively considerable length of the plates 25, 26, retained between the plates 25, 26. It is advantageous, with increasing distance from the injector 14, to make the apertures 28 longer or to increase the number thereof per length unit.

Naturally, also in the case of the example of embodimentaccording to FIG. 1, the formation of the yarn loop legs 17', 17" can be promoted by means of a delimiting element. FIG. 2 shows two elements 23, 24. The latter correspond to the delimiting elements provided with the same reference numerals in FIG. 1.

If this should be desirable, the loop leg 17 can be urged, by supplementary air streams, into the interspace between the plates 25, 26. This may for example be effected by generating, with the aid of the auxiliary nozzles 29, supplementary air streams so directed obliquely away from the slot 27 that they still have a component in the flow direction defined by the injector 14, i.e., are directed in the sense of this flow direction. In order to keep the force or pull-out of the loop 17 at a low level, it is advisable to so control the air stream by the auxiliary nozzles 29 that it is interrupted during pull-out of the loop legs 17, 17".

According to the example of embodiment shown in FIG. 3, there are again provided an injector 14, an eyelet 18, a yarn brake l9 and a weft thread inserter nozzle 20. Air blown out from the injector I4 flows first of all through the chamber 32 which is closed on all sides save for the side opposite the injector 14. The chamber 32 assists in imparting a desired direction to the air stream. Adjacent the open side of the chamber 32 there are provided two elongate plates 33 the broad sides of which are disposed opposite each other and between which there are no lateral walls. A weft thread 11 subjected to the air stream of the injector I4 adopts substantially the loop shape shown in FIG. 3, i.e., it is retained by the air stream in approximately the shape shown. This embodiment is extremely simple in manufacture and is suitable in particular for relatively light and thin weft yarns. The loop leg 17" has per se, due to the guiding thereof through the eyelet 18, the tendency to shift the loop 17 toward the side of the eyelet 18 of the interspace between the plates 33. If this is not sufficient to keep the thread loop apex 35 at least out of the zone of maximum tractive force of the air stream formed by the injector 14, the plates 33 are arranged in conical configuration relative to each other, the plates extending apart from each other from the left to the right in FIG. 3.

A variant of the example of embodiment shown in FIG. 1 may consist in that the shape imparted to the plates 25, 26 is not straight, but curved. In the case of such an embodiment, the plates would be bent over parallel to the plane of symmetry 30 (FIG. 1), so that the symmetrical position of the plates 25, 26 relative to the plane of symmetry 30 is maintained. The arrangement thus resulting is shown in FIG. 4 in which, again, there are shown the injector 14, the thread 11 blown-in by the said injector and the eyelet 18.

The slot 27 is also shown. The upper one of the two plates, visible in FIG. 4, has been given the reference numeral 34. The plates may describe a configuration between a half-circle and a whole circle and they may have the shape of a ring-sector. The mode of operation involved in storage of a yarn piece corresponds to that of the example according to FIG. 1. Optionally, there may again in this instance be provided auxiliary nozzles 29. Due to the bending-over of the plates, the advantage of smaller space requirement is achieved.

It will be seen that the air stream coming from the injector to form the loop and the air stream for inserting the yarn in the shed is supplied from a pressurized air source means 40 through an air supply conduit 42.

It will be appreciated that the application of the present invention is not limited to looms having water or air jets for inserting the pick. It may also be used in advantageous manner on machines employing bars or tapes or having slide-type or gripper-carrier type shuttles.

It will be appreciated further that various changes and modifications may be made within the skill of the art without departing from the spirit and scope of the invention illustrated and described herein.

What is claimed is:

l. A device for the storage of a thread portion of varying length which is subjected to an air stream that retains said thread portion in the form of a loop between a first and a second predetermined location, the end of one of the leg portions of said loop being adjacent to the first predetermined location and the end of the other leg portion of the loop being adjacent to said second predetermined location, an air injector means for continuous delivery of a thread from said first predetermined location to form said loop and means for periodic draw-off of the thread portion from said loop after said loop is formed, said draw-off taking place at said second predetermined location, from which the thread is inserted into a shed of a loom with the aid of weft thread inserter means, there being provided two elongate plates for guiding and shaping the air stream forming said loop, which plates are disposed opposite each other at their broad sides and form an elongated interspace therebetween in the longitudinal direction of which blow-in of the air stream supplied by the injec' tor means takes place and which elongated interspace is open to the outside, forming an open slot along its long side located on the side of said second predeter mined location. I

2. A device according to claim 1 in which said second predetermined location is arranged at a distance from the open slot of said two elongate plates and physically separated from and outside of said two plates.

3. A device according to claim 1 in which said elongated interspace, along its lengthwise side located on the side of said first predetermined location is closed at the inflow location of the air stream forming said loop and open to a progressive extent with increasing distance from the said inflow location.

4. A device according to claim 3 in which there are formed in the longitudinal side, located on the side of said first predetermined location, of the elongated interspace, apertures, the dimensioning of which is such that the apex of the thread loop is located continuously externally ofthe interspace and at a predetermined distance therefrom.

5. A device according to claim 3 in which an auxiliary nozzle means in provided for generating an auxiliary stream of air flowing in said interspace, which said auxiliary stream of air is directed, in relationship to the direction of the air stream forming said loop, obliquely relative thereto and obliquely towards the longitudinal side of the interspace, located on the side of said first predetermined location, and which said auxiliary stream is controllable.

6. A device according to claim 3 in which each of said plates has the shape of a curved ring sector located in one plane to form a curved interspace therebetween.

7. A device according to claim 1 in which said two plates extend in conical configuration towards each other and towards their longitudinal edges located on the side of said second predetermined location.

=l l= =l l 

1. A device for the storage of a thread portion of varying length which is subjected to an air stream that retains said thread portion in the form of a loop between a first and a second predetermined location, the end of one of the leg portions of said loop being adjacent to the first predetermined location and the end of the other leg portion of the loop being adjacent to said second predetermined location, an air injector means for continuous delivery of a thread from said first predetermined location to form said loop and means for periodic draw-off of the thread portion from said loop after said loop is formed, said draw-off taking place at said second predetermined location, from which the thread is inserted into a shed of a loom with the aid of weft thread inserter means, there being provided two elongate plates for guiding and shaping the air stream forming said loop, which plates are disposed opposite each other at their broad sides and form an elongated interspace therebetween in the longitudinal direction of which blow-in of the air stream supplied by the injector means takes place and which elongated interspace is open to the outside, forming an open slot along its long side located on the side of said second predetermined location.
 2. A device according to claim 1 in which said second predetermined location is arranged at a distance from the open slot of said two elongate plates and physically separated from and outside of said two plates.
 3. A device according to claim 1 in which said elongated interspace, along its lengthwise side located on the side of said fiRst predetermined location is closed at the inflow location of the air stream forming said loop and open to a progressive extent with increasing distance from the said inflow location.
 4. A device according to claim 3 in which there are formed in the longitudinal side, located on the side of said first predetermined location, of the elongated interspace, apertures, the dimensioning of which is such that the apex of the thread loop is located continuously externally of the interspace and at a predetermined distance therefrom.
 5. A device according to claim 3 in which an auxiliary nozzle means in provided for generating an auxiliary stream of air flowing in said interspace, which said auxiliary stream of air is directed, in relationship to the direction of the air stream forming said loop, obliquely relative thereto and obliquely towards the longitudinal side of the interspace, located on the side of said first predetermined location, and which said auxiliary stream is controllable.
 6. A device according to claim 3 in which each of said plates has the shape of a curved ring sector located in one plane to form a curved interspace therebetween.
 7. A device according to claim 1 in which said two plates extend in conical configuration towards each other and towards their longitudinal edges located on the side of said second predetermined location. 